Electric switch device



July 5, 1932.

N. RALPH BLEG TRIC SWITCH DEVICE Filed lay 11. 1931 Patented July 5,1932

UNITED STATES PATENT OFFICE NATE RALYH, OF WINONA, MINNESOTA; LAURA J.RALPH ADMINISTRATRIX OF SAID NATE RALPH, DECEASED v nnnc'rnrc swrrcnnnvron A Application filed May 11, 1931. Serial No. 536,634.

The invention relates to a switch mechanism particularly adapted' tocontrol caution and stop si als on street cars, motor busses I or otherve icles.

It is an object of the invention to provide a switch which will cause acaution signal to be given immediately before and after a stop signaland which may be controlled through the actuation of the air brakerigging employed on the car, buss or other vehicle.

A further object of the invention is to provide a novel yieldablecontact coacting with the main movable contact to control the giving ofthe caution signal.

Further objects of the invention will appear from the followingdescription when read in connection with the accompanying drawingshowing an illustrative embodiment of the invention and wherein Fig. 1is a view of the switch mechanism in central longitudinal verticalsection;

Fig. 2 is a sectional view taken on the plane Y of line 2-2 of Fig. 1;

Fig. 3 is a horizontal sectional view taken on the plane of line 33 ofFig. 1; and

Fig. 4 is a diagram of the electrical parts. Referring specifically tothe drawing, a casing is employe at 10 which may be of an suitable size,construction or material. Pre erably such casing has an outer section 11equipped with a removable bottom 12 secured in place by bolts 13. Saidsection 11 is adapted to be suspendedfrom a sill or other part of astreet car, bus or the like, as suggested at 14, being fastened in placeby bolts or the equivalent 15. Enclosed b the section 11 is ,an innersection 16, remova ly resting on lugs 17 rovided on the interior ofsection 11. t one corner of section 16, a block of insulation 18 isanchored to which is fastened a metallic-contact 19 having a bindingpost 20 fastened thereto and extending outwardly through an opening 21in the section 11. An arm or bar 22, preferably of insulation, is hingedat 23 on a horizontal axis, within the section 16, and the same carriesa metallic contact 24 adapted for engagement with the contact 19, suchcontacts 19 and 24 rcfera bly being V-shaped at 25 and 26 at t eir zonesof engagement.

A slack conductor 27 is fastened to a binding post 28 on contact 24 andto a binding post 29 carried by section 16 and projecting outwardlythrough an opening 30 in section 11. The weight of the arm 22 issufficient to enable the same to fall, so that the contacts 19 and 24may engage. In addition, such arm 22 is urged'downwardly by one or morecontractile sp ings fastened thereto and to the bottom wall of thesections The contact 24 is also adapted for engagement with a yieldablecontact 32 which is normally straight and extends horizontally as shownin Figs. 1 and 4. Contact 32 is fastened to the section 16 and has abinding post 33 extending therefrom and through an openin 34 in thesectionill. Depending from the block 22 is a bracket 35 which passesthrough an opening 36 in the bottomwall of section 16 and which pivotallmounts a roller 37 at its lower. end throng the medium of a pin 38.

The switch is normally held in open position through the coaction orengagement of a cam 39 with said roller 37. Said cam 39 forms part of oris carried by a disc or drum 40 located within the section 11 andpivotally mounted by means of a pin 41. Anactuating cable or equivalentflexible element 42 is trained over the periphery of the disc 40 and atboth ends extends exteriorly of the casing and through openings providedtherein at 43.

The mechanism is preferably used in connection with a stop lamp orsignal 44 and a caution lamp or signal 45 located at any suitableposition on the street vehicle.

A telltale lamp 46 is adapted to be illumihated at the same time as lamp44 and a tell-- tale lamp 47 is adapted to be illuminated at the sametime as lamp 45. Said telltale lamps 46 and 47 are located adjacent themotorman or driver of the vehicle for ready observation.

The electric energy for the lamps 44 to 47 is supplied for instance by abattery 48 from one terminal. of which aconductor 49 leads and issecured to the binding post 29. From car, bus or other the otherterminal of the said battery 48, a

conductor 50 leads, which includes the lamps 44 and 46 and which isfastened to the hinding post 20. From the conductor 50, a branchconductor 51 extends to the binding ost 23 and the same includes thelamps 45 an 47.

The cable 42 is adapted to be connected to a suitable movable part ofthe air braking rigging or the equivalent used on the street car ormotor bus but obviously the same may be controlled by any moving part onthe vehicle and in addition be controlled manually or both manually andthrough actuation of an air brake rigging so that in case of failure ofthe air brake rigging, the hand brake may be used to a pl the si a1.

Presuniing operat i dn, the signals 44 to 47 are normally extinct sincethe parts are in the full line position illustrated in Figs. 1 and 4,the switch being held open due to the engagement of cam 39 with roller37. Should the air brake rigging or equivalent part on the street car orbus be moved, a drawing action will be given the cable 42 which willcome spondingly rotate disc 40 and move the cam 39 wholly or partly outof engagement with the roller 37, enabling the arm 22 to gravitatetoward closed position aided by the contractile spring means 31.

Downward movement of the arm 22 first causes engagement of the contacts24 and 32, resulting in illumination of caution signal l5 and telltale47. The contact 32 will bow or yield as suggested by the lower dottedlines in Fig. 1, thus giving the caution signal for a suificiently longperiod.

If the cam 39 completely disengages the roller 37, as when the brakerigging is fully applied, the contact 24 completely disengages thecontact 32 and engages the contact 19, as suggested by. the dotted linesin Fig. 1, thus closing the electric circuit through the stop signal 44:and telltale 46. Upon the disc 40 being noved in the opposite directionby release the brake rigging orthe equivalent cam 39 will reen ageroller 37 thus elevating arm 22 and brea ing the circuit through thestop signal 44 thereupon engaging the contact 32, reestablishing thecircuit through caution signal 45 and then bowing the contact 32 andmoving upwardly past the same whereby all of the signals areextinguished.

Minor changes may be made in the physical embodiment of the inventionwithin the scope of the appended claims without departing from thespirit of the invention.

1 claim:

1. A switch device having relatively movable contacts adapted forengagement, a third contact, all of said contacts being seriallymounted, said third contact being engageable by one of the firstmentioned contacts through said relative movement and having a free enddisposed in the path of said relative movement, said third contact beingyieldable whereby it will be released with a snap action prior toengagement of the first mentioned contacts.

2. A switch device having a first contact,

a second contact movable to engage the same, a third contact to controla different means from that controlled by enga ement of the first andsecond contacts, all 0 said contacts being serially mounted and saidsecond and third contacts extending into the path of movement of eachother and being displaceable one by the other by snap action as thesecond contact is moved into engagement with the first contact.

3. A switch device having a first contact, a .second contact movable toen age the same, a third contact to control a different means from thatcontrolled by enga ement of the first and second contacts, all 0 saidcontacts being serially mounted, said second and third contacts extendininto the path of movement of each other am? being displaceable one bythe other through snap action as thejfjsec- 0nd contact is moved into'engagementwith the first conta t and as the second contact is moved outof engagement with the first contact.

4. A switch device having a casin an arm movably mounted therein providewith a contact, a relatively fixed contact in the casing engageable bythe firstcontact, a yieldable contact in the casing above the fixedcontact engageable by the first contact, said yieldable contact having afree end disposed in the path of movement of the first contact, andbeing movable thereby with snap action,

out of said path, a projection on said arm, contractile spring meansconnected to the arm and casing urging movement of the arm toward thefixed contact, and cam means in the casing below said wall cooperatingwith the projection to control the engagement of said contacts,"

